title: Passive protection of neonatal calves against bovine coronavirus-induced diarrhea by administration of egg yolk or colostrum antibody powder.
abstract: The protective effect of egg yolk and colostrum powders prepared from hens and cows vaccinated with inactivated bovine coronavirus (BCV) antigen was evaluated in a challenge model with a virulent BCV strain. Twenty three calves from BCV-free herds were randomly divided into control and several treatment groups. All calves were orally challenged with 1 x 10(9) TCID50 of the virulent Kakegawa strain of BCV at 24 to 36 h after birth. Calves in treatment groups received either egg yolk powder or cow colostrum containing BCV specific antibodies. Daily treatment with these antibody preparations started 6 h until 7 days post-challenge. Control calves which received no antibody had severe diarrhea and all died within 6 days after infection. In contrast, calves fed milk containing egg yolk or colostrum with neutralization titers of 1:2560 or 1:10,240 respectively all survived and had positive weight gain unlike the other treatment groups. These results indicate that the orally administered egg yolk and colostrum powders protected against BCV-induced diarrhea in neonatal calves and that the egg yolk used provided a higher degree of protection compared to colostrum powder on a titer basis. Treatment with whole egg yolk from immunized hens therefore provides a more efficacious alternative to the existing methods of specific passive protection against BCV.
authors.affiliation: Ghen Corporation Immunology Research Institute, Gifu City, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ikemori
authors.forename: M
authors.initials: M
authors.lastname: Ohta
authors.forename: K
authors.initials: K
authors.lastname: Umeda
authors.forename: F C
authors.initials: FC
authors.lastname: Icatlo
authors.forename: M
authors.initials: M
authors.lastname: Kuroki
authors.forename: H
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Y
authors.initials: Y
authors.lastname: Kodama
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000008:administration & dosage*; D000918:Antibody Specificity; D002417:Cattle; D002418:Cattle Diseases; D003126:Colostrum / Q000821:virology; D018352:Coronavirus Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D017938:Coronavirus, Bovine / Q000276:immunology; D003967:Diarrhea / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D004530:Egg Yolk; D007116:Immunization, Passive / Q000379:methods / Q000662:veterinary*; D009500:Neutralization Tests
chemical_list: D000914:Antibodies, Viral